Overshot fishing tool



Jan. 13,' 1931. E. GRAY ovERsHoT FISHING TooL Filed sept: V19. 1927 mi? 1V l "ya Insuchfcase5 if the fishing too-l has obtained Vfdra'wn from the WellQ.;

Y 1931 i di i .v llilyinvention relates gto improvements: in The body l of my devceis a cylindrical fishing tools for use in welll drilling toteletubular'memberthreaded at Zat its upper end lsoope over and engage pieces'of brokenpipe, for connection withfja collar`3 by means of drill" stemv andsimilar parts :that :have been' which it ,mayr vbe'v engaged lwith ,the tube or lost inthe welll, if -Y c y' Vdrill Asterne,saiddrill' stem extending'up-a In gripping vand withdrawing objects, `w'ardly tothe surfaceiifon operation;L rllhe n suohas pipe, drill stein and similar parts ina lowerend ofthe body'listhreaded at .for v well, itis often o'undthat the object is stuck I connection with a shoel forengagementwith i kin thewell and :cannot be "easily withdrawn.V lthe'pip'e `or drillf'stemV whichv zt'obe with# a irm gripnp'on'theobjectlto Vbewithdrawn, The shoe 6 is cylindrical. on yits'.V outer `:survit'beeomes necessary that thel engagement -beface` and thas anv upperfshank Yhaving a tatwee the tool vangahe Object be.. released so peredathread thereon orlengagement with that the tool. may bevlwithdrawn andother the lower end.y ofthe body" l. Belowft-he 1;, operations entered intowith the/idea of rethreadedshank `Z .there is-'anupwardlygtanl moving the junkfrom the'well. i n peredareaS which is adapted to seat against It is an object of my inventionjto provide the lowerend of the body 1 andL form a firm ya fishing toolof the character noted which supporting engagement between thev ytwo jean be readilyreleased fromfthe object after parts tendingz'to prevent any movement; of j engagement has been made.therewith,and in ythe ishoe'relative tothev body during the use vwhich the gripping meansismadestrong and of the tool.V .The lowerfend of the shoe 'has substantialand .not liable to fail'in use;V f -Y .its inner surface flared `outwardlyyat 9 and'its 'It'is also an'objectto providejmeans to` lower 'end has a sharpbevel 10, thusenabling 'cause apositive and*` firm engagement bef V:the tool to fbetter engage over the upper endof Y,ifs tweenthe shing tool'andtheobject'which ,apipefin the wellf-In addition to the flaring 75 j v.fis engaged. I r inner. surface of`r the shoe 'I have formed 'la Y yIt is another vobject to provide means Yto fnotoh-'orlrecess llin saidslioe, "o'nelsideloutl .lf lclo'seoffthe spacebetween the walls. of the Awhichisv curved. The-other side -13 maybe fishing-tool and the pipe whioh'is engaged vertical, as-illustrated,or also slightly beveled i so vby theftool sothat iiushing fluid may-be or curved." 'ThisV recess in the wall of. theeo i ze shoe on said tool which will enableit-he opershown fo'urioit these dogs; as willfbeapparent an l tool embodyingl myv inventionFig.f-2 is a or enlargement: within theb'odyg. shown at 16j, 95

jpumped downwardlythrough thepipeor shoeiisfformedlatonly-one'place onitslower ff ldrill stemfnpon lwhich'the tool is mounted `side and therefore,prevents theishotriironi` andthe 'return'of liquid inside the-tool may Vengagingwithinthe'upper-endof the brokenr p be prevented;y ltisdesired to form a subpipe. -Thenotch wll'," however, when the A stantialseallbetween the body ofthe tool and tool lismfrotated'enable the operator tofbetter f the object 'whichfis engaged so that there telescope the shoerover ythe` upper end of the may-be no passage of liquid between the tool broken pipe inthe well.- i and-saidobjeet. f T .The :bodylofthe tfol has jon its linner surf Y It isa furtherfobjeot to provide atypeoff faceaplurality of gripping dogs 14. I have `atorto more readily engage the objectlwhich from Fig; 2.y Eachd-og is formed of" anfaristo beremoved. n. Y s ',cnateplatmthelower side of whichisadapted 3 Referring to thedrawing herewith,*Fig..1 to'tfuponashoulder 115 on the inner'wal-l of Y is afcentralvertical section through a .fishing the` b odyfl.VV yAbove. theshoulder is a-recessi transverse section taken on the plane of within which theldog's be. iriwedq.v One f g KK Fig. 1, and Tin-,fthe direction ofthe arrows. Sidevof` eachl dog is shown vasformedjparallel Figf 3 isa bottom` plan view ofthe device with theaxis ofthefbody. ,..Thislis indicated .gf shown,in-Fig,` lillustratingthe formation at' 17 1in? dottedlines inFigfl. :,Theother n K. i 50 'oftbefsboefattached to the,dev'icedf, Vv side oredgelS'is inclinedfrom itsloweredge il n iiexible composition.

upwardly, making the dog smaller at itsupper end than at-its lower end. As will be noted from Fig. 2, the inclined side of the dog is also beveled inwardly. This will be seen at 19 in Fig. 2. `A sharp forward edge 2O is thus formedon the dog Awhich is in the nature of a thread or cutting'face so Ythat when the tool is rotatedv in a right-hand direction, this sharp forward edge at the upper end will Lengage -wi'ththe 'objectjwhich fis gripped and tend to cut int-o the object so as to gradually throw the dogs outwardly as they rotate.

Y Each of the dogsA` is secured. position within the recess'by screws 21 adjacent the lower end, said screws extending through openings in the Vwalls of the body, the heads of the screws fitting within an enlarged recess 22, thusallowing the free play of the screws in said openings to allow movement of the dogs in an obvious manner. Adjacent the upper endsof the "dogs I provide pins 23 which project outwardly from the surface of the dogs and Iserve'. to retain a resilientV thatany resilient member maybe substituted kfor the band, the purpose being to hold the up'perends of the dogs resiliently Ytoward the object which isV to be engaged. Y Y

Above Vthe gripping members I have pro? vided a packer or seal member to engage with theY object which is to be'removed from the well and form a tight closurerbetween the body `and' said obj ect.V Inv the drawing I have 'shown a broken pipe 26 Vwithin the fishing tool and it is to beunderstood that this pipe has been broken ed within Ythe welland the Ytool lhas been telescopedover the upper end thereof. jrThe tool is pushed downwardly over -thebroken pipe until the'dogs 14 engage beneat-h the collar27 upon the pipe.' This collar may be an ordinary coupling or a tool oint or other similar means of connecting the pipe sections in the well. The seal member indi' `cated at 28 is placedabove the gripping dogs a slight distance so that the said seal 'will contact with the eo-uplingv27 and form a` tight closure therewith.- The seal member 28 comprises arin-g or'sleeve of rubber or similar rPhe saidYV sleeve is curved inwardly-between its ends sofasy to form a concave outer face, the inner .face being convex'and adapted to contact with the 'coupling'. At `each end `,of the sleeve 28 the .inner ldiameter thereof is'slightly reduced to receive a metal .ring 29, acting to reinforce the .packing sleeve-and to. 'assist in securing #the said sleeve in position. The inner wall of the body is recessed to receive the sleeve and the I The upper endof the packing sleeve is 'adapt- "ed to'contact'wi'th the-lower end of the coupling member 3, thus assisting in holding the packer in position.

InY the operation of my device, the parts will be assembled `as 'shown in Fig. 1 and the tool wil-lbe introduced into the well at the lower end ,of a pipe or` drill stem l until the broken pipehas been reached. It is usual that the broken pipe stands at an 4angle in the well'leaning against one wall of the well so tl'iat it is difficult to engage theshoe of the iishing tool over the upper en'd of the broken pipe.' By forming the notch `or recess 11 in `the lower end of the pipe at 'one point around the' circumference'thereof, I avoid engaging the body oftheshoe deeply within the upper end of the `'broken pipe, but sufiicient engagement may be made so thatvwhen the fishing tool is'rotated, carrying VtheY lower edge Aof the shoe 64 aroundl against the upper end of the broken'pipe, the edge ofthe shoewi-ll engage thev pipe and carry Vit slightly away from the wall of the well `so that the tool will telescope over the upper end of the pipe. I have found that the notch or recess formed inthe manw ner shown at 11 will effectively' engage the broken pipeeven when ythe said pipe is placed in an awkward position. within the well. y

. Vhen the tool i's engaged over the pipe 'and i is forced downwardly, the upper ends of the .dogs 14 will engage below the lower 'shoulder onkthe collar Y27 of thepipe." The resilient lmember 24 will assure that the dogs rmly gripand hold'the pipe. An upwardmovement is then exerted upon the broken pipe to remove it. If it is found to be firmly lodged and will not move, the 'flushing Huid may :be pumped downwardly through thefdrill stem l and cause it to pass upwardly around the outer side of the broken pipe26 and tend to wash the material away from the outer side thereof, so that it1 may be released from the well. I am enabled to thus wash awaythe 'material outside of the broken'pipe, due to the packingysleeve- 28'.VV ThisV sleeve,"when fixed firmly in its seat within the body l, has an airchamber shown at 31 between the wall 'of the .sleeve and the lrecess in Vwhich it is seated'.` There is a natural resiliency ofthe sleeve bowing it inwardly between its ends against thewallv of the coupling'27. It is found alsoV that thefair chamber l31 formed behind the wallof the sleeve. als'oassists in holding the sleeve rmly against thecollar. `It has been found that heavy pumppressure is en- 2O of the broken pipe'to the surface. l The principal advantages of device lief: Y inthe fact that-it is simple and strong in" I construction and notf'liable tofailinuse and-1YY to itspositive action within the` well. It` isV easily engaged withl thefbrolen' pipe and' im 1y l f ture, thusenabling the operator to wash the claim as new is: K y A 41. A fishing tool comprising a tubular body tirely cut o by the using of aseal'of this nainaterial away from varound the broken pipe.V If it is eventually :found to be impossible to pull the broken pipe from the well even f after it has'been washed, tlie'tool may be re` leased by a rotation thereof ina right-hand' direction. It will be seen that theupper endsv of the dogs 14 bear against the lowershoulder of the collar. The forward edges ofthe dogs Y arev sharpened on" so that they will-engage within the metal of the collar and tendto cut a threador'sliver from thelower'edge of the ibody, a packing k.sleeve of comp-ressible mate.- Vrial abovesaiddogs, said sleeve being Lmount-l collar. This, because of the beveled sidesof the dogs, will tend to force the dogs out-V wardly, crowding them from beneath the coi'- larinto the recess 16 against the action of the i resilient band 24. This will enable thedo'gs to'slip-by the "lower-edge of the collar 27 so that the'device may be pulled upwardly free` again/easily released, and' the sealing sleeve 28 is not liable to' be torn in use and furnishes astrongiand stable packing means capable of' withstanding comparatively vhigh pressures.V my device, what Iv 'Having thus described y having a Adog-receiving recess on its inner side, arcuate dogs inthe saidrecessfmeans'. retaining the lower ends'of said dogsloose/S lyl in saidrecess, means to hold the upper 'ends of said dogsresiliently inwardly, means on the forward edges of saidV dogs beveled ,to

engage the work and cut into the same to forcef p n above saiddogs and adapted to normally close n spect to the work.v f

' 2. A fishing tool includingatubularbody, f

arcuate dogsimounted on the inner face f thereof, means to support said dogs with their upper ends inclined inwardly, said dogs v being tapered upwardlyjand beveled-inwardly, a rforward edge on 'each dogto cut into on said dogs, and an inwardlybowedpaclring sleeve in said body above said dogs,`adaptedV by its own resiliency to make a fluid tightco'ntact with the work. i v

5f. IA .fishing tool including a contact with the'said pipe.

, 6; A' fishing tool including atubularbody, Y

pipe engaging-dogs on the 'inner side of said Y ed upon isaidubody with its ends fixed and the body thereof normally bowed inwardly beftween its ends tocontact with the said pipe,y

theends :of said sleeve being secured to said and saidfsleeve in the manner stated. I

7, Ina fishing'toohav tubular body, are@r` vcesstherein, a tubular packing sleevein said body to formy anairfpocket between lsaidbody. i

recess, said sleeve having itswalls constricted n inwardly `betweenits ends to form. an air ael pocketibetween said' sleeve and-said body, and

in "saidrecess n n 8; In a fishing tool, a body ineinber,a set means/to hold the .ends of said sleeve tightly of fish-engagiiig'dogs mountedk on said body .whereby they will niove longitudinally there with'an"air cushionpacker alsomounted on V n Vsaid vbodyabovesaid dogsand adaptedto-norinally `closeathe area between saidbody and the fish.

9. .In a tool, a body member,a shoulder on said body, aset of fish-engaging dogs 'mountedtoabut said shoulder, whereby they will movelongitudinally therewith, anfair eusliionpacker also mounted' on said body the area Vbetween said body andthe fisli. In testimonyfpwhereof I hereunto afiixfmy signature this 14th-day o f September, AQD.

- ,-y-ELLSWORTHGRAY; y

the surface being gripped, and cause release of the dogs on rotation of saidbody.

3. A fishing tool including a? tubular body, arcuate dogs mounted on the-f inner face' thereof, andineans to'support saiddogs with n their upper ends inclined inwardly, said tool being adapted for rotation in'aclockwisedr "`recti on, forward edges on said 'dogsbeveled inwardly to form worlr engaging portions 1 adapted to force said dogs outwardly when saidtool isrotated.

4. A ishingtool said body, means to retain ,said dogs `loosely onjsaid body, aresilient memberk engaging including a tubular bodyfY arcuate dogs mountedon the inner face o f iis 

